CN111845240A - MPC-based interconnected air suspension cooperative control system and method - Google Patents

MPC-based interconnected air suspension cooperative control system and method Download PDF

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CN111845240A
CN111845240A CN202010594863.1A CN202010594863A CN111845240A CN 111845240 A CN111845240 A CN 111845240A CN 202010594863 A CN202010594863 A CN 202010594863A CN 111845240 A CN111845240 A CN 111845240A
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suspension
optimal
controller
damping coefficient
front left
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CN111845240B (en
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李仲兴
周蓥
于文浩
江洪
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Shaanxi Junuo Technology Co ltd
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Jiangsu University
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60G—VEHICLE SUSPENSION ARRANGEMENTS
    • B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
    • B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
    • B60G17/0152—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by the action on a particular type of suspension unit
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60G—VEHICLE SUSPENSION ARRANGEMENTS
    • B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
    • B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
    • B60G17/019—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by the type of sensor or the arrangement thereof
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60G—VEHICLE SUSPENSION ARRANGEMENTS
    • B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
    • B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
    • B60G17/019—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by the type of sensor or the arrangement thereof
    • B60G17/01933—Velocity, e.g. relative velocity-displacement sensors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60G—VEHICLE SUSPENSION ARRANGEMENTS
    • B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
    • B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
    • B60G17/0195—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by the regulation being combined with other vehicle control systems
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60G—VEHICLE SUSPENSION ARRANGEMENTS
    • B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
    • B60G17/02—Spring characteristics, e.g. mechanical springs and mechanical adjusting means
    • B60G17/04—Spring characteristics, e.g. mechanical springs and mechanical adjusting means fluid spring characteristics
    • B60G17/052—Pneumatic spring characteristics
    • B60G17/0523—Regulating distributors or valves for pneumatic springs
    • B60G17/0525—Height adjusting or levelling valves

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Automation & Control Theory (AREA)
  • Vehicle Body Suspensions (AREA)

Abstract

The invention relates to an interconnected air suspension cooperative control system and method based on MPC (MPC), belonging to the field of semi-active suspension system control of vehicles, wherein the cooperative control system consists of a sensor module, an extended observer module, an MPC controller, a damping coefficient controller, an interconnected state controller, a vehicle body height controller, a damping coefficient executing mechanism, an interconnected state executing mechanism and a vehicle body height executing mechanism; the MPC controller starts from the top layer, always attributes the influence of the damping coefficient, the interconnection state and the vehicle height on the performance to the suspension force provided by each actuating mechanism, takes the optimal suspension performance index as an optimization target, the optimal suspension force is generated by the damping coefficient controller, the interconnection state controller and the vehicle height controller which control the corresponding actuating mechanisms in sequence, the MPC controller is used for solving the optimal suspension force of the system, and then the optimal suspension force is distributed through the damping coefficient, the interconnection state and the vehicle height actuating mechanisms in sequence, so that the control precision is improved, and the MPC controller is suitable for control under any working condition.

Description

MPC-based interconnected air suspension cooperative control system and method
Technical Field
The invention relates to a semi-active suspension system control technology of a vehicle, in particular to a system and a method for cooperatively controlling a damping coefficient, an interconnection state and a vehicle body height of an interconnected air suspension.
Background
As the number of controllable structures in suspension systems increases, coordinated control of damping coefficient, body height, and interconnection state becomes a way to achieve better suspension performance. For example, the document with Chinese patent publication No. CN105082920B proposes a coordinated control system and method for a damping and vehicle height adjustable interconnected air suspension, which firstly make an interconnection state control strategy, a vehicle height control strategy and a damping control strategy, establish a coordinated controller to coordinate the work of the interconnection state control system, the vehicle height control system and the damping control system, correct the control strategy of the interconnection state and the damping coefficient according to a table look-up method by taking the minimum overall vehicle comprehensive performance evaluation index as a target, and finally perform the adjustment of the vehicle height according to the working condition judgment, thereby realizing the coordinated control. However, in the actual running process of the vehicle, the working conditions are complex, only six working conditions are set, and the considered working conditions are few, so that the control precision is poor, and the transportability of the cooperative control according to the control strategy formulated by the table is poor.
MPC (model predictive control) is a rolling optimization control in a limited time domain, and is another branch of the optimal control, which utilizes a system prediction model to predict the future development of the system so as to optimize a control signal, and has the advantages of predicting the state of the future system and being capable of solving the optimal control of the system while taking system constraints into consideration, so that the MPC has more applications in the field of suspension control. The basic principle of model predictive control is based on a model for describing the dynamic behavior of an object, the future dynamics of a system is predicted, an optimization problem is refreshed by using a newly obtained measured value at each sampling moment, the refreshed optimization problem is solved, a first control quantity of the obtained optimization problem acts on the system, and the steps are repeated in a circulating mode, so that the model predictive control comprises three basic steps: (1) predicting future system dynamics based on the prediction model; (2) solving an optimization problem; (3) the first element of the optimization solution is applied to the system.
Disclosure of Invention
The invention provides an interconnected air suspension cooperative control system based on MPC and a control method of the system based on the problems of poor control precision, poor transportability and the like of the existing interconnected air suspension cooperative control, so that the cooperation of the damping coefficient, the interconnection state and the vehicle body height of the interconnected air suspension is realized, and the comprehensive performance of the interconnected air suspension system is further improved.
The technical scheme adopted by the cooperative control system of the interconnected air suspension based on the MPC is as follows: the system comprises a sensor module, an extended observer module, an MPC controller, a damping coefficient controller, an interconnection state controller, a vehicle body height controller, a damping coefficient executing mechanism, an interconnection state executing mechanism and a vehicle body height executing mechanism;
sensor module for measuring stroke speed of front left suspension
Figure BDA0002557160360000021
Front right suspension travel speed
Figure BDA0002557160360000022
Rear left suspension travel speed
Figure BDA0002557160360000023
And rear right suspension travel speed
Figure BDA0002557160360000024
Measuring roll angular velocity
Figure BDA0002557160360000025
Pitch angular velocity
Figure BDA0002557160360000026
And sprung mass acceleration at centre of mass
Figure BDA0002557160360000027
And measuring the front left air spring pressure PflFront and right air spring air pressure PfrRear left air spring pressure PrlAnd rear right air spring pressure PrrInformation, and the front left suspension stroke speed
Figure BDA0002557160360000028
Front right suspension travel speed
Figure BDA0002557160360000029
Rear left suspension travel speed
Figure BDA00025571603600000210
Rear right suspension travel speed
Figure BDA00025571603600000211
Speed of roll angle
Figure BDA00025571603600000212
Pitch angular velocity
Figure BDA00025571603600000213
And sprung mass acceleration at centre of mass
Figure BDA00025571603600000214
Information is transmitted to the extended observer module to obtain the travel speed of the front left suspension
Figure BDA00025571603600000215
Front right suspension travel speed
Figure BDA00025571603600000216
Rear left suspension travel speed
Figure BDA00025571603600000217
Rear right suspension travel speed
Figure BDA00025571603600000218
Transmitting the air pressure P of the front left air spring to a damping coefficient controller flFront and right air spring air pressure PfrRear left air spring pressure PrlAnd rear right air spring pressure PrrConveying to an interconnection state controller and a vehicle body height controller;
vertical displacement Z of sprung mass at centroid estimated by extended observer modulesAnd velocity thereof
Figure BDA00025571603600000219
Vertical displacement Z of front left unsprung massuflAnd velocity thereof
Figure BDA00025571603600000220
Vertical displacement Z of front right unsprung massufrAnd velocity thereof
Figure BDA00025571603600000221
Vertical displacement Z of rear left unsprung massurlAnd velocity thereof
Figure BDA00025571603600000222
Vertical displacement Z of rear right unsprung massurrAnd velocity thereof
Figure BDA00025571603600000223
Road surface excitation q at front left tireflFront right tire road excitation qfrRoad surface excitation q at the position of a left rear tirerlAnd road surface excitation q at the rear right tirerrAnd transmitting to the MPC controller; MPC controller obtains optimal suspension force F ═ FflFfrFrlFrr]And transmitted to a damping coefficient controller, FflOptimum suspension force, F, for the front left suspensionfrFor front-right optimum suspension force, FrlFor rear left optimum suspension force, FrrThe rear right optimum suspension force;
solving by a damping coefficient controller to obtain a front left optimal damping coefficient cfl *Front right optimal damping coefficient cfr *Rear left optimal damping coefficient crl *Rear right optimal damping coefficient crr *Front left optimal suspension force and front left damping force difference Ffl-FDflFront right optimal suspension force and front right damping force difference Ffr-FDfrThe difference F between the rear left optimal suspension force and the front right damping force rl-FDrlThe difference F between the rear right optimal suspension force and the rear right damping forcerr-FDrrAnd the front left optimal damping coefficient c is usedfl *Before, beforeRight optimum damping coefficient cfr *Rear left optimal damping coefficient crl *Rear right optimal damping coefficient crr *Transmitting the difference F between the front left optimal suspension force and the front left damping force to a damping coefficient actuating mechanismfl-FDflFront right optimal suspension force and front right damping force difference Ffr-FDfrThe difference F between the rear left optimal suspension force and the front right damping forcerl-FDrlThe difference F between the rear right optimal suspension force and the rear right damping forcerr-FDrrTransmitting to an interconnection state controller;
solving by the interconnected state controller to obtain the opening time t of the front left interconnected state actuating mechanismIflFront-right interconnection state actuating mechanism opening time tIfrAnd the opening time t of the rear left interconnection state actuating mechanismIrlAnd the opening time t of the rear right interconnection state actuating mechanismIrrAnd the suspension is conveyed to an interconnected state actuating mechanism, and the remaining front left optimal suspension force F is obtained through solvingfl-FDfl-FIflRemaining front right optimum suspension force Ffr-FDfr-FIfrLeft-rear-optimal suspension force Frl-FDrl-FIrlRemaining rear right optimum suspension force Frr-FDrr-FIrrAnd is conveyed to a vehicle body height controller;
the vehicle height controller outputs the opening time t of the front left vehicle height executing mechanismHfl(ii) a Front right body height actuating mechanism opening time tHfrOpening time t of rear left body height executing mechanism HrlOpening time t of rear right body height actuating mechanismHrrTo the body height controller.
The technical scheme adopted by the control method of the interconnected air suspension cooperative control system based on the MPC comprises the following steps of:
step (1): establishing a discretization state space equation of the system, and controlling the state variable and the controlled variable u [ k ] in the discretization state space equation]Constructing a cost function and making a constraint Fmin≤u[k]≤FmaxSolving for the controlled variable u [ k ]]To minimize the cost function, optimizedMPC controller, u [ k ]]＝[FflFfrFrlFrr]，Fmax、FminThe maximum and minimum suspension forces which can be provided by the actuating mechanism of each suspension respectively;
step (2): damping coefficient controller based on front left optimal suspension force FflAnd front left suspension travel speed f' dflCalculating the front left target damping coefficient
Figure BDA0002557160360000031
Damping coefficient c of front left targetaimflMaximum and minimum damping coefficient c with front leftmaxfl、cminflThe front left optimal damping coefficient c is obtained by comparisonflA first step of; calculate front left damping force
Figure BDA0002557160360000032
Judgment of Ffl＞FDflIf not, the process is ended, if so, the damping coefficient controller calculates the difference F between the front left optimal suspension force and the front left damping forcefl-FDflAnd input to the interconnection state controller; obtaining the front right, back left and back right optimal damping coefficients c by the same methodfr *、crl *、crr *Front right, rear left, rear right damping force F Dfr、FDrl、FDrrAnd the difference Ffr-FDfr、Frl-FDrl、Frr-FDrr；
And (3): interconnection state controller base formula
Figure BDA0002557160360000033
Calculating the target value delta P of the air pressure change of the front left air springIaimfl，AeflThe target value delta P is the effective area of the front left air springIaimflThe maximum value and the minimum value delta P of the air pressure of the front left air springmaxfl、ΔPflminThe comparison is carried out to obtain the target optimal value delta P of the air pressure change of the front left air springIflCalculating the opening time t of the actuator in the front left interconnection stateIfl＝ΔPIfl×kI，kIThe time required by the unit air pressure value of the air spring is changed by the interconnection state, and the opening time t of the front right interconnection state actuating mechanism, the rear left interconnection state actuating mechanism and the rear right interconnection state actuating mechanism is obtained by the same methodIfr、tIrl、tIrr；
And (4): the interconnection state controller calculates the suspension force FIfl＝ΔPIfl·Aefl，AeflIs the effective area A of each air springeflJudgment of Ffl-FDfl＞FIflIf the suspension force F is not the optimal suspension force F, the process is ended, and if the suspension force F is the optimal suspension force F, the left optimal suspension force F is leftfl-FDfl-FIflConveying to a vehicle body height controller; the remaining front right, rear left and rear right optimal suspension forces F are obtained by the same methodfr-FDfr-FIfr、Frl-FDrl-FIrl、Frr-FDrr-FIrr；
And (5): the vehicle height controller calculates the target change value of the air pressure of the front left air spring
Figure BDA0002557160360000041
AeflThe target value deltaP will be changed for the effective area of the front left air springaimHflThe maximum value and the minimum value delta P of the air pressure of the front left air springmaxfl、ΔPflminThe comparison results in the optimum value of change Δ PHflCalculating the opening time t of the actuating mechanism for the front left body height Hfl＝ΔPHfl×kH，kHIs the time required by the air spring unit air pressure value of the vehicle body height adjustment.
The invention has the advantages that after the technical scheme is adopted: the MPC controller starts from the top layer, always attributes the influence of the damping coefficient, the interconnection state and the vehicle body height on the performance to the suspension force provided by each actuating mechanism, optimizes and solves the optimal suspension force of the system in a rolling time domain, takes the optimal suspension performance index as an optimization target, the optimal suspension force is generated by the corresponding actuating mechanisms controlled by the damping coefficient controller, the interconnection state controller and the vehicle body height controller in sequence, the optimal suspension force of the system is solved by the MPC controller, and then the optimal suspension force is distributed by the damping coefficient, the interconnection state and the vehicle body height actuating mechanisms in sequence, so that the coordination problem is solved fundamentally, the control precision is improved, and the MPC controller is suitable for control under any working condition.
Drawings
The technical solution of the present invention will be further described in detail with reference to the accompanying drawings and the detailed description.
FIG. 1 is a block diagram of an MPC-based interconnected air suspension cooperative control system according to the present invention;
FIG. 2 is a flow chart of the design of the MPC controller of FIG. 1.
Fig. 3 is a flow chart of a front-left optimal suspension force distribution method according to the present invention.
Detailed Description
Referring to fig. 1, the cooperative control system for the interconnected air suspension based on the MPC of the invention comprises 9 parts, namely a sensor module, an extended observer module, an MPC controller, a damping coefficient controller, an interconnected state controller, a vehicle height controller, a damping coefficient executing mechanism, an interconnected state executing mechanism and a vehicle height executing mechanism. The output ends of the sensor modules are respectively connected with the extended observer module, the damping coefficient controller, the interconnection state controller and the vehicle body height controller. The output end of the MPC controller is connected in series with the damping coefficient controller, the interconnection state controller and the vehicle height controller in sequence. The output end of the damping coefficient controller is connected with the damping coefficient executing mechanism, the output end of the interconnection state controller is connected with the interconnection state executing mechanism, and the output end of the vehicle height controller is connected with the vehicle height executing mechanism. Wherein:
the sensor module consists of four suspension travel speed sensors, a six-axis gyroscope sensor and four air pressure sensors; four suspension stroke speed sensors are respectively arranged at the sprung mass parts of the front left, the front right, the rear left and the rear right, and rocker arms are arranged at the unsprung mass parts of the front left, the front right, the rear left and the rear right for measuring the front left suspension stroke speed
Figure BDA0002557160360000051
Front right suspension travel speed
Figure BDA0002557160360000052
Rear left suspension travel speed
Figure BDA0002557160360000053
And rear right suspension travel speed
Figure BDA0002557160360000054
Information; a six-axis gyroscope sensor is arranged at the projection position of the mass center on the floor and used for measuring the roll angular velocity
Figure BDA0002557160360000055
Pitch angular velocity
Figure BDA0002557160360000056
And sprung mass acceleration at centre of mass
Figure BDA0002557160360000057
Four air pressure sensors are respectively connected with the air spring inflation and deflation air passages of the front left air spring, the front right air spring, the rear left air spring and are used for measuring the air pressure P of the front left air springflFront and right air spring air pressure PfrRear left air spring pressure PrlAnd rear right air spring pressure PrrAnd (4) information. Front left suspension travel speed to be measured by sensor module
Figure BDA0002557160360000058
Front right suspension travel speed
Figure BDA0002557160360000059
Rear left suspension travel speed
Figure BDA00025571603600000510
Rear right suspension travel speed
Figure BDA00025571603600000511
Speed of roll angle
Figure BDA00025571603600000512
Pitch angular velocity
Figure BDA00025571603600000513
And sprung mass acceleration at centre of mass
Figure BDA00025571603600000514
And transmitting the information to the extended observer module. Front left suspension travel speed to be measured by sensor module
Figure BDA00025571603600000515
Front right suspension travel speed
Figure BDA00025571603600000516
Rear left suspension travel speed
Figure BDA00025571603600000517
Rear right suspension travel speed
Figure BDA00025571603600000518
The information is transmitted to the damping coefficient controller. Front left air spring air pressure P to be measured by the sensor moduleflFront and right air spring air pressure PfrRear left air spring pressure PrlAnd rear right air spring pressure PrrAnd the information is transmitted to the interconnection state controller and the vehicle height controller.
The extended observer module processes information output by the sensor module and estimates the vertical displacement Z of the sprung mass at the centroidsAnd velocity thereof
Figure BDA00025571603600000519
Vertical displacement Z of front left unsprung massuflAnd velocity thereof
Figure BDA00025571603600000520
Vertical displacement Z of front right unsprung massufrAnd velocity thereof
Figure BDA00025571603600000521
Rear left unsprung massIs vertically displaced ZurlAnd velocity thereof
Figure BDA00025571603600000522
Vertical displacement Z of rear right unsprung massurrAnd velocity thereof
Figure BDA00025571603600000523
Road surface excitation q at front left tireflFront right tire road excitation qfrRoad surface excitation q at the position of a left rear tirerlAnd road surface excitation q at the rear right tirerr. And the expansion observer module transmits the estimated information to the MPC controller. For expanding the processing method of the observer to the information, refer to the journal Control Engineering Practice published in 2013, volume 21, phase 12, page 1841, 1850, entitled Application of LQ-based sensitivity Control in a vehicle (Unger A, Schimmack F, Lohmann B, and actual Application of LQ-based sensitivity Control in a vehicle [ J].Control Engineering Practice,2013,21(12):1841-1850)。
The input of the MPC controller is the output of the expansion observer module, and the MPC controller processes the input information to obtain the optimal suspension force F, wherein F is [ F ]flFfrFrlFrr]，FflOptimum suspension force, F, for the front left suspensionfrFor front-right optimum suspension force, F rlFor rear left optimum suspension force, FrrFor the rear-right optimum suspension force, the optimum suspension force F is set to [ F ═ FflFfrFrlFrr]And the output signal of the MPC controller is transmitted to the damping coefficient controller.
The input signal of the damping coefficient controller is the optimal suspension force F of the front left suspension output by the MPC controllerflFront right optimum suspension force FfrRear left optimum suspension force FrlRear right optimum suspension force FrrAnd front left suspension travel speed output by the sensor module
Figure BDA0002557160360000061
Front right suspension travel speed
Figure BDA0002557160360000062
Front left suspension travel speed
Figure BDA0002557160360000063
And front and right suspension travel speed
Figure BDA0002557160360000064
A damping coefficient control method is integrated in the damping coefficient controller, and the front-left optimal damping coefficient c is obtained by solving through the damping coefficient control methodfl *Front right optimal damping coefficient cfr *Rear left optimal damping coefficient crl *Rear right optimal damping coefficient crr *Front left optimal suspension force and front left damping force difference Ffl-FDflFront right optimal suspension force and front right damping force difference Ffr-FDfrThe difference F between the rear left optimal suspension force and the front right damping forcerl-FDrlThe difference F between the rear right optimal suspension force and the rear right damping forcerr-FDrr(ii) a The damping coefficient controller adjusts the front left optimal damping coefficient cfl *Front right optimal damping coefficient cfr *Rear left optimal damping coefficient crl *Rear right optimal damping coefficient crr *Transmitting the difference F between the front left optimal suspension force and the front left damping force to a corresponding damping coefficient actuating mechanism fl-FDflFront right optimal suspension force and front right damping force difference Ffr-FDfrThe difference F between the rear left optimal suspension force and the front right damping forcerl-FDrlThe difference F between the rear right optimal suspension force and the rear right damping forcerr-FDrrAnd transmitting to the interconnection state controller.
The input of the interconnected state controller is the difference value F of the front left optimal suspension force and the front left damping force output from the damping coefficient controllerfl-FDflFront right optimal suspension force and front right damping force difference Ffr-FDfrThe difference F between the rear left optimal suspension force and the front right damping forcerl-FDrlRear right optimum suspension forceDifference F from rear right damping forcerr-FDrrAnd front left air suspension pressure P from sensor module outputflFront and right air suspension air pressure PfrRear left air suspension pressure PrlRear right air suspension pressure Prr(ii) a An interconnection state control method is integrated in the system, and the opening time t of the front left interconnection state actuating mechanism is obtained by solving through the interconnection state control methodIflFront-right interconnection state actuating mechanism opening time tIfrAnd the opening time t of the rear left interconnection state actuating mechanismIrlAnd the opening time t of the rear right interconnection state actuating mechanismIrrAnd the suspension is conveyed to an interconnected state actuating mechanism, and the remaining front left optimal suspension force F is obtained through solvingfl-FDfl-FIflRemaining front right optimum suspension force Ffr-FDfr-FIfrLeft-rear-optimal suspension force F rl-FDrl-FIrlRemaining rear right optimum suspension force Frr-FDrr-FIrrAnd is conveyed to a vehicle body height controller;
the input to the body height controller is the remaining front left optimal suspension force F from the output of the interconnected state controllerfl-FDfl-FIflRemaining front right optimum suspension force Ffr-FDfr-FIfrLeft-rear-optimal suspension force Frl-FDrl-FIrlRemaining rear right optimum suspension force Frr-FDrr-FIrrAnd front left air suspension pressure P from sensor module outputflFront and right air suspension air pressure PfrRear left air suspension pressure PrlRear right air suspension pressure PrrThe vehicle height controller is internally integrated with a vehicle height control method, and the opening time t of the front left vehicle height actuating mechanism is obtained through solving by the vehicle height control methodHfl(ii) a Front right body height actuating mechanism opening time tHfrOpening time t of rear left body height executing mechanismHrlOpening time t of rear right body height actuating mechanismHrrAnd delivered to the body height controller.
The damping coefficient actuating mechanism is composed of a front left part,The front left magneto-rheological damper, the front right magneto-rheological damper, the rear left magneto-rheological damper and the rear right magneto-rheological damper respectively adjust the current damping coefficient to the corresponding optimal damping coefficient c according to the signal output by the damping coefficient controllerfl *、cfr *、crl *、crr *。
The interconnection state actuating mechanism consists of four interconnection state normally closed electromagnetic valves of front left, front right, back left and back right, the front left, front right, back left and back right interconnection state normally closed electromagnetic valves open the corresponding interconnection state normally closed electromagnetic valves according to signals output by the interconnection state controller, and the time for opening the electromagnetic valves is t Ifl、tIfr、tIrl、tIrrAnd second.
The vehicle height executing mechanism consists of a front left vehicle height normally closed electromagnetic valve, a front right vehicle height normally closed electromagnetic valve, a rear left vehicle height normally closed electromagnetic valve and a rear right vehicle height normally closed electromagnetic valve, wherein the front left vehicle height normally closed electromagnetic valve, the front right vehicle height normally closed electromagnetic valve, the rear left vehicle height normally closed electromagnetic valve and the rear right vehicle height normally closed electromagnetic valve open corresponding vehicle height normally closed electromagnetic valves according to signals output by the vehicle height controller, and the opening time of the vehicle height normally closedHfl、tHfr、tHrl、tHrrAnd second.
When the control system shown in fig. 1 operates, the MPC controller is first optimized, as shown in fig. 2, and the specific steps for optimizing the MPC controller are as follows:
step 1: establishing a discretization state space equation of the system shown in the formula (1), wherein the formula (1) is that the system state variable x [ k ] at each k sampling time is recurred to the system state variable x [ k +1] at the k +1 th sampling time:
x[k+1]＝Adx[k]+Bduu[k]+Bdωω[k]
y[k]＝Cdx[k]+Dduu[k]+Ddωω[k](1)
the state variable x [ k ] at the kth sampling moment]And system external disturbance ω k]The information is input to the MPC controller; system control u k at the kth sampling time]Is the output of the MPC controller; state variable x [ k +1] at sampling time k +1]Predicting a process quantity in the time domain for the MPC controller; the output quantity y k at the k-th sampling instant]To transmitThe sensor module may measure the quantity. Wherein, at the kth sampling time, the system state variable x [ k ]]Sprung mass displacement Z at centroid for expanding observer module output sAnd velocity thereof
Figure BDA0002557160360000081
Vertical displacement Z of front left unsprung massuflAnd velocity thereof
Figure BDA0002557160360000082
Vertical displacement Z of front right unsprung massufrAnd velocity thereof
Figure BDA0002557160360000083
Vertical displacement Z of rear left unsprung massurlAnd velocity thereof
Figure BDA0002557160360000084
Vertical displacement Z of rear right unsprung massurrAnd velocity thereof
Figure BDA0002557160360000085
At the kth sampling moment, the external disturbance of the system is omega k]Exciting the road surface q at the front left tireflFront right tire road excitation qfrRoad surface excitation q at the position of a left rear tirerlAnd road surface excitation q at the rear right tirerr(ii) a At the kth sampling time, the system control quantity u [ k ]]For each suspension optimum suspension force F, i.e. u k]＝F，F＝[FflFfrFrlFrr]，FflFront left optimal suspension force, F, for front left suspensionfrFor front-right optimum suspension force, FrlFor rear left optimum suspension force, FrrThe rear right optimum suspension force; system output y k at the k-th sampling instant]Is front left suspension stroke speed
Figure BDA0002557160360000086
Front right suspension travel speed
Figure BDA0002557160360000087
Rear left suspension travel speed
Figure BDA0002557160360000088
Rear right suspension travel speed
Figure BDA0002557160360000089
Speed of roll angle
Figure BDA00025571603600000810
Pitch angular velocity
Figure BDA00025571603600000811
And sprung mass acceleration at centre of mass
Figure BDA00025571603600000812
Ad、Bdu、Bdω、Cd、Ddu、DdωIs a matrix of coefficients.
Step 2: constructing a cost function:
the control of the system being aimed at reducing the sprung acceleration at the centre of mass
Figure BDA00025571603600000813
Reduction of tire deformation [ Z ]ufl-qfl，Zufr-qfr，Zurl-qrl，Zurr-qrr]The indexes are passed through the state variable x [ j ] of the jth sampling time of the system]And a control quantity u [ j ] of the jth sampling time ]And corresponding coefficient matrixes Q and R, and converting a control target of the system into a cost function J, wherein the standard form of the cost function J is as follows:
Figure BDA00025571603600000814
x[j]is the system state variable at the jth sampling time, xj]TIs x [ j ]]Transposing; u [ j ]]The control quantity of the jth sampling moment is; u [ j ]]TIs u [ j ]]Transposing; q and R are each x [ j ]]And u [ j ]]K +1, k +2, k +3 … k + p, p being the prediction step size.
And step 3: formulating system constraints
MPC controlControl quantity u [ k ] of output of device]Need to satisfy Fmin≤u[k]≤FmaxWherein F ismaxIs the maximum suspension force, F, that the actuator of each suspension can providemax＝[FflmaxFfrmaxFrlmaxFrrmax]，FflmaxMaximum suspension force, F, available for the actuator in the front left suspensionfrmaxMaximum suspension force, F, available for the actuator in the front right suspensionrlmaxMaximum suspension force, F, available for the actuator in the rear left suspensionrrmaxThe maximum suspension force that can be provided by the actuator in the rear left suspension; fminIs the minimum suspension force that each actuator can provide. Fmin＝[FflminFfrminFrlminFrrmin]，FflminMinimum suspension force, F, available for the actuator in the front left suspensionfrminMinimum suspension force, F, available for the actuator in the front right suspensionrlminMinimum suspension force, F, available for the actuator in the rear left suspensionrrminThe maximum suspension force that can be provided by the actuator in the rear right suspension.
Combining the discretized state space equation of equation (1) and the cost function J of equation (2), the optimization problem of the system is described as follows:
Figure BDA0002557160360000091
constrained to:
x[k+1]＝Adx[k]+Bduu[k]+Bdωω[k](3)
Fmin≤u[k]≤Fmax
the formula (3) is built in an MPC controller, a quadratic programming solver is arranged in the MPC controller, and the optimization problem is solved through the quadratic programming solver, namely, the controlled variable u [ k ] is solved to minimize the cost function J under the condition that the system state variable and the controlled variable meet the discrete state space equation and the system constraint.
The control system shown in FIG. 1 operates with an optimized MPC controller and the amount of control output by the optimized MPC controller is controlledQuantity u [ k ]]For each suspension optimum suspension force F, u k]＝F＝[FflFfrFrlFrr]Then converting F to [ F ]flFfrFrlFrr]Input to the damping coefficient actuator. As shown in fig. 3, the front left optimal suspension force process obtained by the damping coefficient actuator, the interconnected state actuator and the body height actuator distributed MPC controller will be described below by way of example at the front left of the interconnected air suspension system. The conditions of the front right, the rear left and the rear right of the interconnected air suspension system are the same as those of the front left of the interconnected air suspension. The method comprises the following specific steps:
step 1: the damping coefficient controller outputs the front left optimal suspension force F according to the optimized MPC controller flAnd front left suspension travel speed output by the sensor module
Figure BDA0002557160360000092
Calculating a front left target damping coefficient c according to equation (4)aimfl：
Figure BDA0002557160360000093
Then, the front left target damping coefficient caimflMaximum and minimum damping coefficient c with front leftmaxfl、cminflThe front left optimal damping coefficient c is obtained by comparisonflA first step of; the method comprises the following steps:
judging the front left target damping coefficient caimfl＞cmaxfl-cminflWhether or not it is established, cmaxflIs the maximum damping coefficient of the front left magneto-rheological shock absorber, cminflIs the minimum damping coefficient of the front left magneto-rheological shock absorber, if so, the front left optimal damping coefficient cfl *＝cmaxfl-cminfl(ii) a If not, then judging that c is more than or equal to 0aimfl≤cmaxfl-cminflWhether the damping coefficient is established or not, if so, the front-left optimal damping coefficient cfl *＝caimfl(ii) a If not, judging c againaimflIf < 0 is true, the front-left optimal damping coefficient cfl0; the correction formula is (5))：
Figure BDA0002557160360000101
In the same way, the front right optimal damping coefficient cfr *Rear left optimal damping coefficient crl *Rear right optimal damping coefficient crr *Obtaining method and front-left optimal damping coefficient cfl *The obtaining method is the same.
Damping coefficient controller calculates front left optimal damping coefficient cfl *Meanwhile, the damping coefficient controller outputs the front left optimal damping coefficient cfl *Speed of front left suspension
Figure BDA0002557160360000102
Multiplying to obtain a front left damping force FDflThe calculation formula is (6):
Figure BDA0002557160360000103
obtaining front right, back left and back right damping forces F by the same method Dfr、FDrl、FDrr。
Front left optimum damping coefficient cfl *The damping coefficient is input into a damping coefficient execution mechanism, and a front left magnetorheological damper in the damping coefficient execution mechanism adjusts the current damping coefficient to a front left optimal damping coefficient cfl *。
Step 2: damping coefficient controller judges Ffl＞FDflWhether the result is true or not; if Ffl＞FDflIf not, the process is ended. If Ffl＞FDflIf yes, the damping coefficient controller calculates the difference F between the front left optimal suspension force and the front left damping forcefl-FDflAnd the difference Ffl-FDflAnd inputting the data into an interconnection state controller.
Similarly, the difference F between the front right optimal suspension force and the front right damping forcefr-FDfrRear left optimum suspension force and front right dampingDifference of force Frl-FDrlThe difference F between the rear right optimal suspension force and the rear right damping forcerr-FDrrIs obtained from the difference F between the left optimal suspension force and the front left damping forcefl-FDflThe obtaining method is the same.
And step 3: the interconnection state controller outputs a difference value F between the front left optimal suspension force and the front left damping force according to the damping coefficient controllerfl-FDflAnd the front left air suspension air pressure P measured by the sensor moduleflCalculating a target value delta P of the air pressure change of the front left air spring caused by the change of the interconnection stateIaimflThe calculation formula is the following formula (7):
Figure BDA0002557160360000104
in the formula, AeflIs the effective area of the front left air spring.
Then, the target value Δ P is set IaimflMaximum value delta P of air pressure of front left air springmaxflAnd is the minimum value delta P of the change of the air pressure of the front left air springflminThe comparison is carried out to obtain the target optimal value delta P of the air pressure change of the front left air springIflThe method specifically comprises the following steps:
determination of Δ PIaimfl＞ΔPmaxflWhether or not it is established, Δ PmaxflIs the maximum value of the air pressure of the front left air spring, and if so, the change in interconnection conditions causes the optimal value of the air pressure change of the front left air spring Δ PIfl＝ΔPmaxfl(ii) a If not, then determining Δ Fmaxfl≤ΔPIaimfl≤ΔPminflWhether or not, Δ PflminIs the minimum value of the change of the air pressure of the front left air spring, if so, the delta PIfl＝ΔPIaimfl(ii) a If not, then determining Δ PIaimfl＜ΔPminflIf so, Δ PIfl＝ΔPminfl(ii) a The correction formula is formula (8);
Figure BDA0002557160360000111
according toCalibrating the time k required by the interconnection state to change the unit air pressure value of the air springIAnd the optimal value delta P of the air spring air pressure change caused by the change of the interconnection stateIflCalculating the opening time t of the normally closed electromagnetic valve in the front-left interconnection stateIfl＝ΔPIfl×kl。
Front-right interconnection state actuating mechanism opening time tIfrAnd the opening time t of the rear left interconnection state actuating mechanismIrlAnd the opening time t of the rear right interconnection state actuating mechanismIrrThe method for obtaining the same.
The interconnected state controller calculates the opening time t of the interconnected normally closed electromagnetic valveIflSimultaneously, the optimal value delta P of the air spring air pressure change caused by the change of the interconnection state IflAnd effective area A of each air springeflMultiplying to obtain the suspension force F caused by the change of the interconnection stateIflThe calculation formula is (9):
FIfl＝ΔPIfl·Aefl(9)
the interconnected state controller conveys the opening time t of the front left interconnected normally closed electromagnetic valveIflTo the interconnected state actuating mechanism, and the front left interconnected state normally closed electromagnetic valve in the interconnected state actuating mechanism is opened tIflAnd second.
Then, the interconnection state controller judges Ffl-FDfl＞FIflWhether the result is true or not; if not, the process is ended; if so, the interconnection state controller calculates the remaining optimal suspension force Ffl-FDfl-FIflAnd delivered to the body height controller.
The remaining front right, rear left and rear right optimal suspension forces F are obtained by the same methodfr-FDfr-FIfr、Frl-FDrl-FIrl、Frr-FDrr-FIrr。
And 4, step 4: the body height controller controls the optimal suspension force F left according to the left-front residual input by the interconnection state controllerfl-FDfl-FIflAnd the air pressure P of the front left air spring measured by the sensor moduleflInformation, calculation to obtain body height adjustmentCausing the air pressure in the front left air spring to change by a target value delta PaimHflThe calculation formula is (10);
Figure BDA0002557160360000121
in the formula, AeflIs the effective area of the front left air spring.
Then, the determination of Δ PaimHfl＞ΔPmaxflIf it is true, then the change in body height causes a change in air pressure in the front left air spring by an optimum amount Δ PHfl＝ΔPmaxfl(ii) a If not, then determining Δ P maxfl≤ΔPaimHfl≤PminflIf true, Δ PHfl＝ΔPaimHfl(ii) a If not, determine Δ PaimHfl＜ΔPminflIf true, Δ P if trueHfl＝ΔPminfl(ii) a The correction formula is (11);
Figure BDA0002557160360000122
adjusting the time k required by the unit air pressure value of the air spring according to the calibrated vehicle body heightHChange of air pressure of air spring caused by change of height of vehicle bodyHflCalculating the opening time t of the actuating mechanism for the front left body heightHfl＝ΔPHfl×kH. Obtaining the opening time t of the front right vehicle body height actuating mechanism by the same methodHfrOpening time t of rear left body height executing mechanismHrlOpening time t of rear right body height actuating mechanismHrrTo the body height controller. Knowing the opening time t of the normally closed electromagnetic valve of the vehicle body heightHflVehicle body height controller delivery tHflTo the corresponding vehicle body height normally closed electromagnetic valve, and the corresponding vehicle body height normally closed electromagnetic valve is opened tHflAnd second, ending the process.
Because the MPC controller takes into account the constraint of the damping coefficient, the interconnection state and the maximum value of the sum of the suspension forces that the body height actuator is capable of providing, the MPC outputs the front-left optimal suspension force FflCan finish the distribution through the damping coefficient, the interconnection state and the vehicle height actuating mechanism at the front left part, so the rest suspension force F can be used in the vehicle height control linkfl-FDfl-FIflAnd generation is carried out without judgment.
The conditions of the front right, the rear left and the rear right of the interconnected air suspension are the same as those of the front left of the interconnected air suspension. Therefore, for the optimization problem of the interconnected air suspension cooperative control system, the MPC controller solves the obtained control quantity u [ k ], namely the optimal suspension force F; the damping coefficient, the interconnection state and the suspension force provided by the vehicle body height executing mechanism are sequentially generated, and the cooperative control of the damping coefficient, the interconnection state and the three controllable structures of the vehicle body height is realized, so that the sprung mass acceleration at each part is reduced, the suspension moving stroke and the tire deformation at each part are reduced, the riding comfort is improved, and the road friendliness is improved.
The present invention is not limited to the above-described embodiments, and any obvious improvements, substitutions or modifications can be made by those skilled in the art without departing from the spirit of the present invention.

Claims (7)

1. An interconnection air suspension cooperative control system based on MPC is characterized in that: the system comprises a sensor module, an extended observer module, an MPC controller, a damping coefficient controller, an interconnection state controller, a vehicle body height controller, a damping coefficient executing mechanism, an interconnection state executing mechanism and a vehicle body height executing mechanism;
Sensor module for measuring stroke speed of front left suspension
Figure FDA0002557160350000011
Front right suspension travel speed
Figure FDA0002557160350000012
Rear left suspension travel speed
Figure FDA0002557160350000013
And rear right suspension travel speed
Figure FDA0002557160350000014
Measuring roll angular velocity
Figure FDA0002557160350000015
Pitch angular velocity
Figure FDA0002557160350000016
And sprung mass acceleration at centre of mass
Figure FDA0002557160350000017
And measuring the front left air spring pressure PflFront and right air spring air pressure PfrRear left air spring pressure PrlAnd rear right air spring pressure PrrInformation, and the front left suspension stroke speed
Figure FDA0002557160350000018
Front right suspension travel speed
Figure FDA0002557160350000019
Rear left suspension travel speed
Figure FDA00025571603500000110
Rear right suspension travel speed
Figure FDA00025571603500000111
Speed of roll angle
Figure FDA00025571603500000112
Pitch angular velocity
Figure FDA00025571603500000113
And sprung mass acceleration at centre of mass
Figure FDA00025571603500000114
Information is transmitted to the extended observer module to obtain the travel speed of the front left suspension
Figure FDA00025571603500000115
Front right suspension travel speed
Figure FDA00025571603500000116
Rear left suspension travel speed
Figure FDA00025571603500000117
Rear right suspension travel speed
Figure FDA00025571603500000118
Transmitting the air pressure P of the front left air spring to a damping coefficient controllerflFront and right air spring air pressure PfrRear left air spring pressure PrlAnd rear right air spring pressure PrrConveying to an interconnection state controller and a vehicle body height controller;
vertical displacement Z of sprung mass at centroid estimated by extended observer modulesAnd velocity thereof
Figure FDA00025571603500000119
Vertical displacement Z of front left unsprung massuflAnd velocity thereof
Figure FDA00025571603500000120
Vertical displacement Z of front right unsprung massufrAnd velocity thereof
Figure FDA00025571603500000121
Vertical displacement Z of rear left unsprung massurlAnd velocity thereof
Figure FDA00025571603500000122
Vertical displacement Z of rear right unsprung massurrAnd velocity thereof
Figure FDA00025571603500000123
Road surface excitation q at front left tireflFront right tire road excitation qfrRoad surface excitation q at the position of a left rear tirerlAnd road surface excitation q at the rear right tirerrAnd transmitting to the MPC controller; MPC controller obtains optimal suspension force F ═ FflFfrFrlFrr]And transmitted to a damping coefficient controller, FflOptimum suspension force, F, for the front left suspensionfrFor front-right optimum suspension force, FrlFor rear left optimum suspension force, FrrThe rear right optimum suspension force;
solving by a damping coefficient controller to obtain a front left optimal damping coefficient cfl *Front right optimal damping coefficient cfr *Rear left optimal damping coefficient crl *Rear right optimal damping coefficient crr *Front left optimal suspension force and front left damping force difference Ffl-FDflFront right optimal suspension force and front right damping force difference Ffr-FDfrThe difference F between the rear left optimal suspension force and the front right damping forcerl-FDrlThe difference F between the rear right optimal suspension force and the rear right damping forcerr-FDrrAnd the front left optimal damping coefficient c is usedfl *Front right optimal damping coefficient cfr *Rear left optimal damping coefficient crl *Rear right optimal damping coefficient crr *Transmitting the difference F between the front left optimal suspension force and the front left damping force to a damping coefficient actuating mechanismfl-FDflFront right optimal suspension force and front right damping force difference F fr-FDfrThe difference F between the rear left optimal suspension force and the front right damping forcerl-FDrlThe difference F between the rear right optimal suspension force and the rear right damping forcerr-FDrrTransmitting to an interconnection state controller;
solving by the interconnected state controller to obtain the opening time t of the front left interconnected state actuating mechanismIflFront-right interconnection state actuating mechanism opening time tIfrAnd the opening time t of the rear left interconnection state actuating mechanismIrlAnd the opening time t of the rear right interconnection state actuating mechanismIrrAnd is conveyed to each otherConnecting a state execution mechanism, and solving to obtain the residual front left optimal suspension force Ffl-FDfl-FIflRemaining front right optimum suspension force Ffr-FDfr-FIfrLeft-rear-optimal suspension force Frl-FDrl-FIrlRemaining rear right optimum suspension force Frr-FDrr-FIrrAnd is conveyed to a vehicle body height controller;
the vehicle height controller outputs the opening time t of the front left vehicle height executing mechanismHfl(ii) a Front right body height actuating mechanism opening time tHfrOpening time t of rear left body height executing mechanismHrlOpening time t of rear right body height actuating mechanismHrrTo the body height controller.
2. A method of controlling an MPC-based interconnected air suspension coordinated control system as recited in claim 1, comprising the steps of:
step (1): establishing a discretization state space equation of the system, and controlling the state variable and the controlled variable u [ k ] in the discretization state space equation ]Constructing a cost function and making a constraint Fmin≤u[k]≤FmaxSolving for the controlled variable u [ k ]]Minimizing the cost function to obtain an optimized MPC controller, u k]＝[FflFfrFrlFrr]，Fmax、FminThe maximum and minimum suspension forces which can be provided by the actuating mechanism of each suspension respectively;
step (2): damping coefficient controller based on front left optimal suspension force FflAnd front left suspension travel speed
Figure FDA0002557160350000021
Calculating the front left target damping coefficient
Figure FDA0002557160350000022
Damping coefficient c of front left targetaimflMaximum and minimum damping coefficient c with front leftmaxfl、cminflThe front left optimal damping coefficient c is obtained by comparisonflA first step of; meterCalculating front left damping force FDfl＝cfl *·fdflJudgment of Ffl＞FDflIf not, the process is ended, if so, the damping coefficient controller calculates the difference F between the front left optimal suspension force and the front left damping forcefl-FDflAnd input to the interconnection state controller; obtaining the front right, back left and back right optimal damping coefficients c by the same methodfr *、crl *、crr *Front right, rear left, rear right damping force FDfr、FDrl、FDrrAnd the difference Ffr-FDfr、Frl-FDrl、Frr-FDrr；
And (3): interconnection state controller base formula
Figure FDA0002557160350000031
Calculating the target value delta P of the air pressure change of the front left air springIaimfl，AeflThe target value delta P is the effective area of the front left air springIaimflThe maximum value and the minimum value delta P of the air pressure of the front left air springmaxfl、ΔPflminThe comparison is carried out to obtain the target optimal value delta P of the air pressure change of the front left air springIflCalculating the opening time t of the actuator in the front left interconnection state Ifl＝ΔFIfl×kI，kIThe time required by the unit air pressure value of the air spring is changed by the interconnection state, and the opening time t of the front right interconnection state actuating mechanism, the rear left interconnection state actuating mechanism and the rear right interconnection state actuating mechanism is obtained by the same methodIfr、tIrl、tIrr；
And (4): the interconnection state controller calculates the suspension force FIfl＝ΔPIfl·Aefl，AeflIs the effective area A of each air springeflJudgment of Ffl-FDfl＞FIflIf the suspension force F is not the optimal suspension force F, the process is ended, and if the suspension force F is the optimal suspension force F, the left optimal suspension force F is leftfl-FDfl-FIflConveying to a vehicle body height controller; the remaining front right, rear left and rear right optimal suspension forces F are obtained by the same methodfr-FDfr-FIfr、Frl-FDrl-FIrl、Frr-FDrr-FIrr；
And (5): the vehicle height controller calculates the target change value of the air pressure of the front left air spring
Figure FDA0002557160350000032
AeflThe target value deltaP will be changed for the effective area of the front left air springaimHflThe maximum value and the minimum value delta P of the air pressure of the front left air springmaxfl、ΔPflminThe comparison results in the optimum value of change Δ PHflCalculating the opening time t of the actuating mechanism for the front left body heightHfl＝ΔPHfl×kH，kHIs the time required by the air spring unit air pressure value of the vehicle body height adjustment.
3. The method of claim 2, wherein the method further comprises the steps of: in the step (2), the damping coefficient controller judges the front left target damping coefficient c firstaimfl＞cmaxfl-cminflWhether the damping coefficient is established or not, if so, the front-left optimal damping coefficient c fl *＝cmaxfl-cminflIf not, then judge 0 ≦ caimfl≤cmaxfl-cminflWhether the damping coefficient is established or not, if so, the front-left optimal damping coefficient cfl *＝caimflIf not, then judging caimflIf < 0 is true, the front-left optimal damping coefficient cfl*＝0。
4. The method of claim 3 for controlling an MPC based interconnected air suspension coordinated control system, wherein: in the step (3), the interconnection state controller firstly judges the delta PIaimfl＞ΔPmaxflIf so, the optimal value of the front left air spring air pressure change Δ PIfl＝ΔPmaxflIf not, then determining Δ Pmaxfl≤ΔPIaimfl≤ΔPminflWhether or not the above-mentioned conditions are satisfied,if so, Δ PIfl＝ΔPIaimflIf not, then determining Δ PIaimfl＜ΔPminflIf so, Δ PIfl＝ΔPminfl。
5. The method of claim 4 for controlling an MPC based interconnected air suspension coordinated control system, wherein: in the step (5), the vehicle body height controller firstly judges delta PaimHfl＞ΔPmaxflIf so, the change of the air pressure of the front left air spring is changed by the optimal value delta PHfl＝ΔPmaxflIf not, then determining Δ Pmaxfl≤ΔPaimHfl≤ΔPminflIf true, Δ PHfl＝ΔPaimHflIf not, determining Δ PaimHfl＜ΔPminflIf it is true, the optimum value Δ P is changedHfl＝ΔPminfl。
6. The method of claim 2, wherein the method further comprises the steps of: in the step (1), the discretization state space equation of the system is as follows:
x[k+1]＝Adx[k]+Bduu[k]+Bdωω[k]，
y[k]＝Cdx[k]+Dduu[k]+Ddωω[k]，
x[k]For the system state variable x k at the sampling instant k]，x[k+1]Is the system state variable at the sampling time k +1, ω k]External disturbance omega k of middle system]，u[k]To control the quantity, y [ k ]]Is the system output quantity at the kth sampling time, x k]Sprung mass displacement Z at centroid for expanding observer module outputsAnd velocity thereof
Figure FDA0002557160350000042
Vertical displacement Z of front left unsprung massuflAnd velocity thereof
Figure FDA0002557160350000043
Vertical displacement Z of front right unsprung massufrAnd velocity thereof
Figure FDA0002557160350000044
Vertical displacement Z of rear left unsprung massurlAnd velocity thereof
Figure FDA0002557160350000045
Vertical displacement Z of rear right unsprung massurrAnd velocity thereof
Figure FDA0002557160350000046
External disturbance of system omega k]Exciting the road surface q at the front left tireflFront right tire road excitation qfrRoad surface excitation q at the position of a left rear tirerlAnd road surface excitation q at the rear right tirerr(ii) a Control quantity u [ k ]]For each suspension optimum suspension force F, u k]＝F＝[FflFfrFrlFrr]The system output y [ k ]]The front left, front right, rear left and rear right suspension travel speeds
Figure FDA0002557160350000047
Speed of roll angle
Figure FDA0002557160350000048
Pitch angular velocity
Figure FDA0002557160350000049
And sprung mass acceleration at centre of mass
Figure FDA00025571603500000410
Ad、Bdu、Bdω、Cd、Ddu、DdωIs a matrix of coefficients.
7. The method of claim 6 wherein the method further comprises the steps of: cost function
Figure FDA0002557160350000041
x[j]Is the system state variable at the jth sampling time, xj]TIs x [ j ]]Transpose of u [ j ]]Is the control quantity at the jth sampling time u [ j ] ]TIs u [ j ]]Transposing; q and R are each x [ j ]]And u [ j ]]K +1, k +2, k +3 … k + p, p being the prediction step size.
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112757860A (en) * 2021-01-25 2021-05-07 江苏大学 NMPC-based hub direct-drive air suspension system and cooperative control method
CN113239450A (en) * 2021-03-11 2021-08-10 华南理工大学 Interconnected air suspension multi-objective optimization method based on interval analysis
CN113815369A (en) * 2021-09-18 2021-12-21 江苏大学 Interconnected air suspension cooperative control system and control method based on multiple intelligent agents
CN114056027A (en) * 2021-12-15 2022-02-18 苏州凯瑞汽车测试研发有限公司 Vehicle height and damping cooperative control method for air suspension
CN114590090A (en) * 2022-03-04 2022-06-07 江苏大学 Direct-drive semi-active suspension control system construction method based on self-adaptive LQR (Low-speed response) wheel hub
CN114953881A (en) * 2022-05-31 2022-08-30 小米汽车科技有限公司 Vehicle control method, device, vehicle, storage medium and chip

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105082920A (en) * 2015-08-05 2015-11-25 江苏大学 Cooperative control system and method for damping-adjustable and vehicle body height-adjustable interconnection air suspension
CN107323198A (en) * 2017-06-09 2017-11-07 江苏大学 A kind of laterally interconnection air suspension interconnection state Fuzzy control system and method
CN107985004A (en) * 2017-11-02 2018-05-04 江苏大学 A kind of laterally interconnection air suspension resistance of shock absorber game-theoretic control system
CN108891221A (en) * 2018-07-24 2018-11-27 山东大学 A kind of active suspension system and its working method based on mode energy distribution method
CN109203903A (en) * 2017-07-06 2019-01-15 丰田自动车株式会社 Suspension control system
CN109774399A (en) * 2019-01-15 2019-05-21 南昌大学 A kind of hydraulic interconnection suspension semi-active control method of road surface excited frequency range identification
CN110001341A (en) * 2019-03-05 2019-07-12 江苏大学 A kind of air suspension transverse direction interconnected control systems and method

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105082920A (en) * 2015-08-05 2015-11-25 江苏大学 Cooperative control system and method for damping-adjustable and vehicle body height-adjustable interconnection air suspension
CN107323198A (en) * 2017-06-09 2017-11-07 江苏大学 A kind of laterally interconnection air suspension interconnection state Fuzzy control system and method
CN109203903A (en) * 2017-07-06 2019-01-15 丰田自动车株式会社 Suspension control system
CN107985004A (en) * 2017-11-02 2018-05-04 江苏大学 A kind of laterally interconnection air suspension resistance of shock absorber game-theoretic control system
CN108891221A (en) * 2018-07-24 2018-11-27 山东大学 A kind of active suspension system and its working method based on mode energy distribution method
CN109774399A (en) * 2019-01-15 2019-05-21 南昌大学 A kind of hydraulic interconnection suspension semi-active control method of road surface excited frequency range identification
CN110001341A (en) * 2019-03-05 2019-07-12 江苏大学 A kind of air suspension transverse direction interconnected control systems and method

Cited By (7)

* Cited by examiner, † Cited by third party
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CN112757860B (en) * 2021-01-25 2022-07-22 江苏大学 NMPC-based hub direct-drive air suspension system and cooperative control method
CN113239450A (en) * 2021-03-11 2021-08-10 华南理工大学 Interconnected air suspension multi-objective optimization method based on interval analysis
CN113815369A (en) * 2021-09-18 2021-12-21 江苏大学 Interconnected air suspension cooperative control system and control method based on multiple intelligent agents
CN114056027A (en) * 2021-12-15 2022-02-18 苏州凯瑞汽车测试研发有限公司 Vehicle height and damping cooperative control method for air suspension
CN114590090A (en) * 2022-03-04 2022-06-07 江苏大学 Direct-drive semi-active suspension control system construction method based on self-adaptive LQR (Low-speed response) wheel hub
CN114953881A (en) * 2022-05-31 2022-08-30 小米汽车科技有限公司 Vehicle control method, device, vehicle, storage medium and chip

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